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Updated: May 10, 2026
11:49
Characterization of G Protein-coupled Receptors by a Fluorescence-based Calcium Mobilization Assay
Published on: July 28, 2014
Minireview: Nutrient sensing by G protein-coupled receptors
Eric M Wauson1, Andrés Lorente-Rodríguez, Melanie H Cobb
1Department of Pharmacology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390-9041, USA.
Molecular Endocrinology (Baltimore, Md.)
|July 4, 2013
Summary
Amino acids are detected by class C G protein-coupled receptors (GPCRs), regulating cellular decisions. The umami taste receptor T1R1/T1R3 senses amino acid availability, impacting mTOR activity.
Area of Science:
- Biochemistry
- Cell Biology
- Molecular Biology
Background:
- G protein-coupled receptors (GPCRs) are crucial cell surface proteins mediating signal transduction.
- Amino acids serve as essential building blocks, metabolic substrates, and energy sources for cells.
- Specific GPCRs, particularly Class C, are involved in sensing extracellular molecules like amino acids.
Purpose of the Study:
- To review findings on Class C GPCRs sensing amino acids and sweet molecules.
- To highlight the role of the umami taste receptor (T1R1/T1R3) in amino acid sensing.
- To discuss the regulation of physiological processes by these receptors.
Main Methods:
- Literature review of studies on Class C GPCRs.
- Analysis of receptor-ligand interactions for amino acids and sweet molecules.
- Examination of signaling pathways regulated by these GPCRs, including mTOR.
Main Results:
- Class C GPCRs, including umami and sweet taste receptors, GPRC6A, and the calcium-sensing receptor, detect amino acids.
- The umami taste receptor heterodimer T1R1/T1R3 acts as a sensor for amino acid availability.
- Amino acid sensing by T1R1/T1R3 regulates the activity of the mammalian target of rapamycin (mTOR).
Conclusions:
- Class C GPCRs play a significant role in sensing extracellular amino acids and related molecules outside of neuronal tissues.
- Amino acid availability, detected by receptors like T1R1/T1R3, influences critical cellular processes such as mTOR signaling.
- This sensing mechanism is vital for context-specific cellular decision-making and physiological regulation.
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